On a short ride out to fetch something from the local sorting office, I noticed a burning smell. I didn't think much of it as the bike hasn't been run in a while and I figured it was some crap burning off the engine or exhaust. However a little later, on taking it out again, I noticed the Tach won't read over 5000 RPM. I was wondering what could've caused this. Is the tach cable knackered, or is it something in the engine messed up? Any ideas?

Sorry mate, it beats me. Though that's a bit odd; not goin over 5k